Modern chairs often include backs and seats that are capable of several functional motions about multiple planes of motion. In particular, many chairs include underseat motion control mechanisms to provide independent sliding, pivoting and rocker motions that allow components to move in a particular way relative to the seated user so as to provide an optimally comfortable and adjustable chair motion. However, these control mechanisms tend to be complex control mechanisms that require several independent external actuators to perform the motional functions. Furthermore, such control mechanisms tend not to act in simultaneous response to varying movements and postures of a seated user. Instead, the control mechanisms often require independent actuator activation, and they tend to respond independently of one another. Further, the independently actuated mechanisms take up space and can become structurally large in size. This is less desirable for chairs requiring a simple profile or otherwise requiring a clean unobstructed area under their seat. Also, design of these mechanisms is a complex task, with substantial time required to understand and work out competing functional requirements and physical relationships between motion mechanisms.
Accordingly, it is desirable to provide a seat with a motion control mechanism having the aforementioned advantages and solving the aforementioned problems. More particularly, it is desirable to provide a seat control that facilitates synchronous rocking and reclining motion in response to user movement. It is also desirable to provide a seat control that provides appropriate mechanisms to prevent over-motion of the chair. In particular, it is desirable to provide suitable controls for resisting or damping excessive roll, yaw, fore-aft and side-to-side translation of the chair relative to ground. It is also desirable to provide a control mechanism that employs few or no external actuators. It is also desirable to provide a relatively small, compact control mechanism.
The present invention is provided to solve the problems discussed above and other problems, and to provide advantages and aspects not previously provided. A full discussion of the features and advantages of the present invention is deferred to the following detailed description, which proceeds with reference to the accompanying drawings.